1. Field of the Invention
Embodiments of the present invention relate to methods and systems for converting thermal energy from low temperature sources, especially from low temperature geothermal sources, into mechanical and/or electrical energy.
More particularly, embodiments of the present invention relate to methods and systems for converting thermal energy from low temperature sources, especially from low temperature geothermal sources, into mechanical and/or electrical energy, where a working fluid comprises a mixture of at least two components. In certain embodiments the working fluid comprising a water-ammonia mixture. Embodiments of the present invention also relate to novel thermodynamic cycles or processes and systems to implement them.
2. Description of the Related Art
Prior art methods and systems for converting heat into useful energy at well documented in the art. In fact, many such methods and systems have been invented and patented by the inventor. These prior art systems include U.S. Pat. Nos. 4,346,561, 4,489,563, 4,548,043, 4,586,340, 4,604,867, 4,674,285, 4,732,005, 4,763,480, 4,899,545, 4,982,568, 5,029,444, 5,095,708, 5,440,882, 5,450,821, 5,572,871, 5,588,298, 5,603,218, 5,649,426, 5,822,990, 5,950,433; 5,593,918; 6,735,948; 6,769,256; 6,820,421; and 6,829,895; incorporated herein by reference.
Although all of these prior art systems and methods relate to the conversion of thermal energy into other more useful forms of energy from moderately low temperature sources, all suffer from certain inefficiencies. Thus, there is a need in the art for an improved, economically systems and methods for converting thermal energy from moderately low temperature sources to more useful forms of energy, especially for converting geothermal energy from moderately low temperature geothermal streams into more useful forms of energy.